Dye coating composition for color photography



Patented Dec. 30, 1947 DIEZCOATINGTCOMPOSITION FOR COLORw PHOTOGRAPHY" Richard? M2 Haft,.Binghamton, N. Y., assignori torGeneral Aniline & Film Corporation; New York-,;.N.Y., alcorporation of Delaware;

No Drawing; Application'August 31'; 1944, Serial No. 552,209-

5 Claims. (Cl. 106-22) Thisrinv-ention relatesito color photography,-

and more particularly to a process of=:.converting black and. white or monochrome: drawings into colored. drawings; Specifically; the invention contemplatesrdyee coating compositionsforcoloringiblaolctand white negatives:

In preparing colored drawings'from an original black-line: or: monochrome-drawing; the process employed is" to copy'on photograph a black and whitezor'rmonochrome drawing I on a photographic film. After development, .washing and drying of the .explosedzfilm', the=' negativeis' laid on a glass illuminated from-:belovrand: dye coating: solutions appliedrto theatransparentgllnes'and areas of the negative which. are: to appear in color in the finished: print; The colors: of the dye solutions employed areacomplementary to the colors desired in thefinal print'. To obtaininthe final print, aaline or arealof 'anycolor, for'example; green, the line or: areain the negative is dyedwith'a color complementary t'o green, namely, magenta. The system may be best understood by reference to the following table:

Color desired in'finished- Color'ot dye'applied to film production negative "Green: 7

4 leitmicolored.

Asphotographic paper: consisting of threeemul sions, coated on a.supp ort-,. each. emulsion layer; sensitive. to :light. otone ofthe=-colors, red,v green and: blue, and: each layer. containing, at, color forming compound, is exposed ina printing frame in:- contact. with: the. emulsion surfaceof the colored: negative-:torwhite lightwith; or without the-use {of-filters -overstheilightsource; The dyes? in thelinessor areas. of the negative serve as color: filters, which. are in. generaladequate to. print lines of satisfactory-colon andJpuritywithout the;

use of additionaltfilters.v A single exposure; is.

sufiicient to print all of the coloredllines After exposure,. the. photographic. color paper: is; then developed in a. p phenylenediamine typee devel-v oper, the reaction products of which coupleiwi-th;

No :dyer needed: The: negative isthe color. forming compoundsycontainediin theemulsion layers-of the photographic color paper, to give aflprint compposedpof lines-lor areaswhich are 1 complementary to the colored: lines. or areas. of thenegative...

The developmentaoizthe above process has been attended. with difficulties connected with the applicationof the-dye coating: compositions to the transparent} linesior areas of the negative which are to appearsin color in the-finished print. The aqueous: or: alcohohsolutionsof: the dyes previously used are notsatisfactory: forcoloring the negatives, since they are diflicult toapply in sufficient density with reasonablespeed: Furthermore; crystallization of, the; dyev takes place upondrying; These dyesolutions also a have a tendencyi-tozrun; after. application; into unevenareas resultingin? the formation of: areasofunequal density so thatiuneven color lines or areas are obtained in--.the.-fiinshed print.

It isan: objectof r the; present? invention to overcome these andother undesirable characteristics and disadvantages; and.- to provide, improveddye coating compositions, whereby colored negativesof desirablecharacteristic are obtained;

A further: object is. to provide a. simplified processof converting black: and ,white-or mono!- chrome drawings-into. multicolor photographs;

Other objects :and advantages ofrthis. invention will. be apparent; byreference to the foregoing specification; in: which its: preferred details and embodiments are described:

The. objects; outlined: above are; accomplishedv: by employing dye coating compositions. of the.

following general? composition;

Grams 1-1 0 Water soluble. dye; 15 to 35% aqueous. solution ofcomplex.

sodium borophosphate 50- 10!) The complex sodium borophosphate referred to, in the above general compositioniseither. a, noncrystalline water soluble glasssolid obtained by fusing an. alkali metal. phosphate. with. an, oxygen containing compoundsof. boron. as de scribed. in U. S. Patent 2,291,958, or. awater soluble viscous ,solutionobtainedby heating aqueous;so1utions of. monosodium: phosphate and an.

alkali metal borate as describedin; U. S;'Bate1;t 241 .641; Th sqlidison cntofi tneaquemis 111- tions prepared by either method may range from to 35% or more by weight. The preferred concentration for the purpose of the present invention is one that contains 15% by weight of the solid complex sodium borophosphate.

In the above general composition any commercially available water soluble dye may be employed. The nature of the dye is immaterial so long as it is water soluble and gives the desired colorimetric result. In general, the most satisfactory water soluble dyes are found in the group of dyes classified under the usual constitutional headings, which are grouped in the following list:

Acridine dyes, e. g., Acridine OrangeR (C. I. #792), Phosphine 2G (C. I. #794), 'Euchrysine 26 (C. I. #797), etc., Anthraquinone dyes, e; Alizarin Carmine (C. I. #1034), Erwece Alizarin Acid Red SB (C. I. #1036), Pseudopurpurin ((3.1. #1043), etc., Azine dyes, e. g., Neutral Red (C. I. #825), Neutral Violet (C. I. #876), Rosinduline Q (C. I. #831), etc., Azo dyes, e. g., Emin Red (C. I. #132), Metanil Yellow (C. I. #138), Ericchrome Phosphine R (C. I. #157), Fast-light Yellow (C. I, #636), Kiton Fast Yellow 3G (C. I.

#645), Pyrazolorange G (C. I. #653), Chlorazol Yellow GX (C. I. #620),I Cotton Orange 6305 (C. I. #625), Direct Fast Orange BGL (C. I. #633), etc., Nitro dyes, e. g., Victoria Yellow (C. I. #8), Naphthol Yellow (C. I. #10), Amido Yellow (C. I. #11), etc., Oxazine dyes, e. g., Bril liant Blue CC (C. I. #876), Chromazurine E (C. I. #879) etc., Thiazine dyes, e. g., Genthianine (C. I. #921) Methylene Azure '(C. I. #923), Indo chromogen S (C. I. #930), and Triphenyl methane dyes, e. g., Turquiso Blue G (C. I. #661), Acid Green (C. I. #669),Xylene Blue AS (0.1 #673) and the like. a V r The above dyes were selected because of their brilliancy of color. The preferred dyes from the above group, however, are those which effectively transmit a sharply isolated spectral band while eliminating undesirable transmissions of a secondary spectral band. Thus, for example, the red dye which may be a mixture of Anthra quinone Rubine and Tartrazine, transmits freely in the red wave length beyond 600 m and is substantially opaque to the spectral region below 600 m The green dye. which may be a mixture of Anthraquinone Blue SE and Tartrazine N transmits freely in the green wave length between 500 and 600 m and is substantially opaque to other spectral regions. The blue dye which may be amixture of Anthraquinone Blue SE andFast Acid Violet B transmits freely in the blue wave length between 400 and 500 m and is substantially opaque to the longer wave lengths of the spectrum. The orange dye such as Pyrazolorange .G transmits above 500 m and is substantially opaque to the shorter wave lengths of the spectrum. The magenta dye such as Anthraquinone Rubine transmits freely two bands, one in. the

blue region of 400-500 mp. and the other band in dye coating composition, coloring a negative and printing it out On color paper.

The cyan dyes suitable for forming red lines 01 4 areas in the finished print are, for example, Anthraquinone Blue SE (Schultz #861), Brilliant Alizarin Viridine F (Schultz #854) and Alizarin Cyanine Green F (Schultz #865) The yellow dyes suitable for forming the blue lines or areas in the finished print are, for example, Pyrazolorange G (Schultz #747), Stilbene Yellow 3GA (C. I. #622), Milling Yellow (Schultz #230), Erie Yellow Y (C. I. #365), Solantine Yellow FF (C. I. #814), Naphthol Yellow S (Schultz #7) and Tartrazine N (Schultz #23).

-The magenta dyes suitable for forming the green lines or areas in the finished print are, for example, Brilliant Congo G (Schultz #369), Geranine GL, Erie Pink 2B (C. I. #128), Rose Bengal N (Schultz #595), Anthraquinone Rubine R (DuPont), Brilliant Purpurine 4B (Schultz #368) and Brilliant Crocein B (Schultz #227).

Several red dyes may be obtained by blending magentadyes with yellow dyes. Suitable greens may be obtained by blending cyan dyes with yellow dyes. Suitable blue-violets may be obtained by blending cyan dyes with violet or magenta dyes. Similarly, the hue of the single dyes, yellow, magenta and cyan, may be adjusted to the requirements of the color paper by blending two dyes: together.

The amount of dye employed in each coating composition will depend upon the amount of the aqueous complex sodium borophosphate used and the depth of shade required. The amount employed may range from 1 to 10 grams per grams of the aqueous complex sodium borophosphate., ,The desirable proportions, however, are in the range of 3 to 5 grams per 100 grams of aqueous complex sodium borophosphate.

The aqueous solution of the complex sodium borophcsphate acts as a vehicle for the dyes. The amount employed may range from 50 to 100 grams per 1-10grams of the water soluble dye.

In carrying out the invention into practice the aqueous solution of the complex sodium borophosphate is heated gently at a temperature not exceeding 50 C. with stirring for a few minutes and then allowed to cool. In preparing the dye desired-weight. Although substantially all of the water soluble dyes listed above are compatible with the aqueous solution of complex sodium 'borophosphate, a few isolated instances occurred where a slight difficulty was encountered in completelydissolving the dye In such a case I have found that by lowering the pH of the aqueous solution of the complex sodium borophosphate from about 7.0 to a pH ranging from 5.0 to 4.0 by'the addition of a small quantity of a water soluble organicacid containing from 2 to 6 carbon atoms such as; for example, acetic, acrylic, citric, malonic, oxalic, tartaric and the like, solutions are obtained in which the dye is readily and completely dissolved. The amount of acid em ployed may vary from 5 to 15 parts per 100 parts of the aqueous solution of the complex sodium borophosphate. Although any one of the acids listed above may be employed for lowering of the DH, the use of acetic acid, in view of its low cost, is preferred.

The following examples are illustrative of the are-prepared; M I

. Theaqueous solution eicomplex'sodium bdrophos hate employediimhxample II-waspunchased 911113116 open market under the trade-name of Abopon andiipresumably madeaaccording toth'e process described inU. .S. Patent.2;143s,64l. The aqueous solution or" :;complex 1 sodium iborophosphate. employed in Examples I fand .pre pared-according to .Example '7 of U. S. Patent 2911958 by fusing '2 'mols of :sodiuinhEXd'rhltaphosphate with3 mols' of'bora'x and shock-chillingthe resulting melt. Fifteen grams of the .glassy solid was dissolved in'water 'and the volume brought upto 100 to.

EXAMPLE vI "-("Bluewiolet are) Grams Complex sodium borophos'phate 45% solution .1106) Qtnthraquinone Blue-35E tschultz #861) v 3:!) FalstTAcidViolet B lSGh ultz #580) 1.5

EXAMPLE '11 (Yellow dye.)

V V Grams Complex sodium borophcsphate 35% solution 50 Pyrazolorange G (Schultz-#7417) :2.=.'ll

* EXAMPIIE'III V Mogentaadye) V Gra'ms Complex sodium borophosphate solution 100 BrllliantkCongoiG fischultz t do lnr 3 A specific example of'empl-oyingthef aboveliye' coating compositions in the preparation of "a-col-' ored film negative for color printing is the following:

A drawing of an electrical circuit in india ink was copied on a high contrast photographic film so as to obtain high densities and clean White lines. After exposure, the film was developed in the usual developing solution, fixed, washed and dried. The dried negative was then temporarily cemented emulsion downwards on a piece of glass. The film negative and glass were then placed on a light table in a reasonably level position. The light table was fitted with daylight fluorescent tubes in order to obtain desirable color quality for judgment, of color densities. The film negative was then cleaned with a cloth moistened with ethyl alcohol in order to prepare it for even dyeing.

The above blue-violet, yellow and magenta dye coating compositions were then applied evenly over the white lines of the negative which are to appear as yellow, blue and green respectively in'the final print. The dye coating solutions were applied by means of a small spotting brush, the sharp needle point of which was cut off, so as to confine the dye substantially to the line being colored; that is, without substantially overlapping the white line, or forming areas of excess dye adjoining the white line. One application with the brush fully charged with each of the dyes to the lines being colored was adequate to obtain sufficient color density. The applied dye coating solution was permitted'to flow naturally in order to obtain even spreading. Between colors, the brush was rinsed, in a glass of water and dried on a cloth. After application of the dyes, 3 to 5 minutes were required for iexaimination of' theabove colored negative that-rtlie dye coatings were thoroughly dryiahdniidcnot crackmor did-the dyes crystaliize iout. cAlli'the-bo-lored lines were -satisfactorily smooth :and even; *The "colored negative was then'bontact printed on :a 'three super-imposed emulsion layer rphotographic color paper, emul 'sion i emulsion :in a [printing :fra-me, six reet frbmea ull-watt, frosted mazda lamp. The exposu-re time was approximatelyaloseconds. :The exposedc'olor paper was thendeveloped in a develope'raoftthefollowing composition:

After bleachi'ri'g, fixing, i-washingand drying, the

resultingprintishowed .no unevennessin the coloredl'ines. the'coloredilines were smooth and pure color. a i

The photographic multilayer element (color paper) 'iorlot-her printi ng material used in carryingoi'itlthegprocess described in the present-invention vconsists-ofIan integral tripack emulsion coated an eithr'the usual paper base, or a clear cellulose-acetatebr nitrate film base, or in some cases an opaque white film base. Each of the emulsionlayers -is sensitized to one of the primary colors oillight namely, blue,- green and red. The top layer is blue sensitive. Afilter layer, yellow in color and blueabsorbing lies under-the top layer. 5 Below this filter layer lies a green sensitive emulsion layer, and below this a red sensitive emu-lsionlayer. :Each of the threezsilvar-halide emulsion -layers contain dye-forming compounds which unite during the development of a silver image in anaromatic amine-developing agent to form a dye with the oxidation product of the developing agent. As silver is also formed during development, it must be removed after color development by treatment in a bleach followed by a bath of sodium thiosulfate, as is well known to the art. A yellow dye is formed in the blue sensitive emulsion; a magenta dye is formed in the green sensitive emulsion; and a cyan dye is formed in the red sensitive emulsion. The combinations of these three printing primaries yield red, green, blue and black lines. Suitable methods for the preparation of multicolor emulsion layers have been described in the literature relating to color photography and are, therefore, not described here.

The dye coating compositions of the present invention are not limited to the coloring of a black and white film negative given above, such being merely illustrative of the manner of employing the dye coating compositions of this inventi-on.

Instead of coating black and white negatives, the dye coating compositions of the present invention may be employed for making colored transparencies from black and white or blueprint drawings. In this process, a thin and flat transparent medium such as paper, organic ester of cellulose, superpolyamide, polyester or synthetic resin, is superimposed over a black and 7 white or blue-print drawing, and the various lines or areas which are to appear in color are inked or coated with the dye coating compositions. After drying the transparency, it is then removed from the original drawing and printed on color paper as hereinbefore described.

The dye coating compositions may also be employed for retouching or repairing damaged areas of colored photographs such as transparencies or paper prints. The Various dye coating compositions may be mixed on a piece of opal glass with a small brush to match theprevailing color of the area surrounding the blemish. The dye is then applied with the brush to the blemish. On drying, the dye will assume the surface characteristics of the gelatine image-bearing layer, and the repaired or retouched area will not be readily detectable.

While I have herein disclosed the preferred embodiments of my invention, I do not thereby desire or intend to limit myself solely to the specific examples, since it will be readily apparent to those skilledin the art, that the precise proportions of the materials utilized may be varied and other materials having equivalent chemical or physical properties may be employed if desired without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims.

Iclaim:

1. A dye coating composition for color photography, consisting of. 50 to 100 parts by weight of a 15-35% aqueous solution of a complex sodium borophosphate, containing 1 to parts by weight of a water soluble synthetic organic dyestuff selected from the class consisting of anthraquinone and sulfonated azo dyes.

2. A dye coatin composition for color photography, consisting of 1 to 10 parts by weight of a water soluble synthetic organic dyestuff selected from the class consisting of anthraquinone and sulfonated azo dyes, dispersed in a vehicle medium consisting of 50 to 100 parts by weight of a -35% aqueous solution of a complex sodium borophosphate acidified with a water soluble organic acid containing from 2 to 6 carbon atoms to a pH ranging from 5.0 to 4.0.

4. A dye coating composition for color photography consisting of a dispersion of:

Grams Complex sodium borophosphate 35% aqueous solution Pyrazolorange G (Schultz #747) 2.0

5. A dye coating composition for color photography consisting of a dispersion of:

Grams Complex sodium borophosphate 15% aqueous solution Brilliant Congo G (Schultz #369) 3.0

RICHARD M. I-IAFF.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,304,072 Medl Jan. 25, 1944 2,356,065 Keating Aug. 15, 1944 2,126,504 Reynolds Aug. 8, 1939 2,093,738 Reynolds Sept. 21, 1937 OTHER REFERENCES Drug and Specialty Formulas, Belanger, Chemical Publishing Co.. Inc., Brooklyn, N. Y., 1941, page 97. 

